The present invention relates to a multi-step positioning device of a trunk pull rod, which is especially suitable to a pull rod fixing means being adjusted steplessly.
Traveling for business or other purposes is prevailed currently, and thus trunks becomes a required tool in traveling. Telescopic pull rods are important components in the design of a trunk, which can provide great convenience to the travelers. Since the height of everyone is different, while it is preferred that the trunk is pulled by an angle of 45 degrees. In order to meet various demands, two sectional or multiple sectional pull rods are preferred and are widely used. Rods with two sections and one operation step is generally used in the design of trunks. Namely, after the upper section of the pull rod is pulled out, only the lower end of the upper sectional rod and the upper end of the lower sectional rod is positioned. The use of each sections of the rods is not well designed. There are some difference according to the height of the trunk. Therefore, a three sectional rod or a four sectional rod is designed. However, the operation of these multi-sectional rod is not preferred since it can not be fine adjusted. Therefore, a multi-sectional or stepless structure is designed. Furthermore, the positioning of the two sectional rod is not confined in a single position. Many positions serves to position the rod. Even every position is usable. The positions for positioning is conventionally installed with continuous holes. However, this will deteriorate the outlook, and weak the structure. In another design, the positioning structure is installed in the rod. FIG. 7 shows a prior art structure. A positioning piece 1 is installed in the outer rod. The positioning piece 1 is installed with a bank of positioning holes 11 for achieving the object of multiple step adjustment for satisfying the requirement of the user. As shown in the figure, the positioning piece is necessary to be installed in the rod, therefore, a buckling structure is installed in the outer rod 2, in which a pair of inward protruding strips 11 are used. Although the shape of the outer rod 2 has a long elliptic shape, the inner rod has a square shape, and therefore, the visual feeling is effected. Another, the outer rod is a rectangular rod, while the inner rod is a square rod, but this is not good in visual feeling, since square rod looks very bulky. Thus, it is not met the requirement of compactness and it has many defects. Besides, a pull rod adjusting means of gears and racks is designed, wherein the gear must be adjusted precisely for positioning. It is inconvenient to the user. Furthermore, the whole structure is heavy and is almost not used commercially. An adjusting rod of teeth block and rack is designed, further. Although it has the advantages of steplessness, the application is limited. Too many adjustments cause the user not to select it properly. However, from the experiences of the applicant, there are a great extent in the design of the pull rod to satisfy the requirement of consumers.
Accordingly, the primary object of the present invention is to provide a multi-step positioning device of a trunk pull rod for using the space of the pull rod more efficiency so that the original two rod types are converted to a multiple rod type. Furthermore, elliptic rods are used instead of the conventional square rods. By the space between inner and outer rods to clamp the porous piece, the shape of the porous piece is formed as cambered rod for using space sufficient. Besides, the spring buckling buckling device is used to be buckled with the porous piece. Therefore, most of the requirement in use is satisfied. Moreover, the porous piece of the present invention is matched with a handle to be adjusted in positions so that the whole structure is more convenient.
Another object of the present invention is to provide a multi-step positioning device of a trunk pull rod, which can be used in the adjustment of a third sectional rod. Each section is used in an optimum condition. Each rod is retained in a specific shape for saving space.
In the present invention, A multi-step positioning device of a trunk pull rod has a pair of pull rods at two sides thereof. Each pull rod has an inner upper rod and an outer lower rod therein. The rod body has two sides of round arc shapes. After engaging the round arc portions of the two rods are formed with gaps. Porous pieces are placed in the gaps. The porous piece passes through the outer lower rod. The upper end of the outer lower rod is connected to an upper rod sleeve. Protruding buckles at two sides of the upper rod sleeve buckles with the buckling holes with respect to the outer lower rod. The lower end of the inner upper rod is connected to a lower rod sleeve. The slender end of the lower rod sleeve passes through the inner upper rod. The enlarged end portion has a part identical to the inner upper rod for being engaged with the porous piece. The enlarged end portion has a part having an inner diameter identical to that of the outer lower rod for being passing through the outer lower rod. The middle rod sleeve has a sliding groove at the lateral surface thereof for being inserted by a sliding block and a spring. The sliding block is connected to a driving piece. The driving piece passes through the inner upper rod to be connected to the pull piece of the handle.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when reading in conjunction with the appended drawing.